Finger injury. Could use some feedback?

i think you have too much pressure on the part of your finger that has the blister. you need a better molded bowling ball or some change in technique to get the pressure off that spot. an mri is basically worthless for what you have. now if you twist that area it is possible to have a chronic "sprain" to that joint too. but with blister formation and open sore i think it is more likely to be the first premise. jantje